/Engine/Source/Runtime/AudioExtensions/Public/IAudioEndpoint.h
For endpoints that override EndpointRequiresCallback to return true, this callback will be called every (GetDesiredNumFrames()/GetSampleRate()) seconds.
whether the endpoint is still valid. If this returns false, DisconnectAllInputs will be called automatically.
virtual bool OnAudioCallback ( const [TArrayView](API\Runtime\Core\Containers\TArrayView)< const float > & InAudio, const int32 & NumChannels, const [IAudioEndpointSettingsProxy](API\Runtime\AudioExtensions\IAudioEndpointSettingsProxy) * InSettings )